1 /* Copyright (C) 2010-2012 B.A.T.M.A.N. contributors:
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of version 2 of the GNU General Public
7 * License as published by the Free Software Foundation.
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
23 #include "soft-interface.h"
24 #include "gateway_client.h"
25 #include "originator.h"
27 #include "translation-table.h"
29 #include "hard-interface.h"
32 static struct sk_buff *frag_merge_packet(struct list_head *head,
33 struct frag_packet_list_entry *tfp,
36 struct unicast_frag_packet *up =
37 (struct unicast_frag_packet *)skb->data;
38 struct sk_buff *tmp_skb;
39 struct unicast_packet *unicast_packet;
40 int hdr_len = sizeof(*unicast_packet);
41 int uni_diff = sizeof(*up) - hdr_len;
43 /* set skb to the first part and tmp_skb to the second part */
44 if (up->flags & UNI_FRAG_HEAD) {
51 if (skb_linearize(skb) < 0 || skb_linearize(tmp_skb) < 0)
54 skb_pull(tmp_skb, sizeof(*up));
55 if (pskb_expand_head(skb, 0, tmp_skb->len, GFP_ATOMIC) < 0)
58 /* move free entry to end */
61 list_move_tail(&tfp->list, head);
63 memcpy(skb_put(skb, tmp_skb->len), tmp_skb->data, tmp_skb->len);
66 memmove(skb->data + uni_diff, skb->data, hdr_len);
67 unicast_packet = (struct unicast_packet *)skb_pull(skb, uni_diff);
68 unicast_packet->header.packet_type = BAT_UNICAST;
73 /* free buffered skb, skb will be freed later */
78 static void frag_create_entry(struct list_head *head, struct sk_buff *skb)
80 struct frag_packet_list_entry *tfp;
81 struct unicast_frag_packet *up =
82 (struct unicast_frag_packet *)skb->data;
84 /* free and oldest packets stand at the end */
85 tfp = list_entry((head)->prev, typeof(*tfp), list);
88 tfp->seqno = ntohs(up->seqno);
90 list_move(&tfp->list, head);
94 static int frag_create_buffer(struct list_head *head)
97 struct frag_packet_list_entry *tfp;
99 for (i = 0; i < FRAG_BUFFER_SIZE; i++) {
100 tfp = kmalloc(sizeof(*tfp), GFP_ATOMIC);
102 batadv_frag_list_free(head);
107 INIT_LIST_HEAD(&tfp->list);
108 list_add(&tfp->list, head);
114 static struct frag_packet_list_entry *frag_search_packet(struct list_head *head,
115 const struct unicast_frag_packet *up)
117 struct frag_packet_list_entry *tfp;
118 struct unicast_frag_packet *tmp_up = NULL;
119 uint16_t search_seqno;
121 if (up->flags & UNI_FRAG_HEAD)
122 search_seqno = ntohs(up->seqno)+1;
124 search_seqno = ntohs(up->seqno)-1;
126 list_for_each_entry(tfp, head, list) {
131 if (tfp->seqno == ntohs(up->seqno))
134 tmp_up = (struct unicast_frag_packet *)tfp->skb->data;
136 if (tfp->seqno == search_seqno) {
138 if ((tmp_up->flags & UNI_FRAG_HEAD) !=
139 (up->flags & UNI_FRAG_HEAD))
148 list_move_tail(&tfp->list, head);
152 void batadv_frag_list_free(struct list_head *head)
154 struct frag_packet_list_entry *pf, *tmp_pf;
156 if (!list_empty(head)) {
158 list_for_each_entry_safe(pf, tmp_pf, head, list) {
167 /* frag_reassemble_skb():
168 * returns NET_RX_DROP if the operation failed - skb is left intact
169 * returns NET_RX_SUCCESS if the fragment was buffered (skb_new will be NULL)
170 * or the skb could be reassembled (skb_new will point to the new packet and
173 int batadv_frag_reassemble_skb(struct sk_buff *skb, struct bat_priv *bat_priv,
174 struct sk_buff **new_skb)
176 struct orig_node *orig_node;
177 struct frag_packet_list_entry *tmp_frag_entry;
178 int ret = NET_RX_DROP;
179 struct unicast_frag_packet *unicast_packet =
180 (struct unicast_frag_packet *)skb->data;
184 orig_node = orig_hash_find(bat_priv, unicast_packet->orig);
188 orig_node->last_frag_packet = jiffies;
190 if (list_empty(&orig_node->frag_list) &&
191 frag_create_buffer(&orig_node->frag_list)) {
192 pr_debug("couldn't create frag buffer\n");
196 tmp_frag_entry = frag_search_packet(&orig_node->frag_list,
199 if (!tmp_frag_entry) {
200 frag_create_entry(&orig_node->frag_list, skb);
201 ret = NET_RX_SUCCESS;
205 *new_skb = frag_merge_packet(&orig_node->frag_list, tmp_frag_entry,
207 /* if not, merge failed */
209 ret = NET_RX_SUCCESS;
213 batadv_orig_node_free_ref(orig_node);
217 int batadv_frag_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv,
218 struct hard_iface *hard_iface, const uint8_t dstaddr[])
220 struct unicast_packet tmp_uc, *unicast_packet;
221 struct hard_iface *primary_if;
222 struct sk_buff *frag_skb;
223 struct unicast_frag_packet *frag1, *frag2;
224 int uc_hdr_len = sizeof(*unicast_packet);
225 int ucf_hdr_len = sizeof(*frag1);
226 int data_len = skb->len - uc_hdr_len;
227 int large_tail = 0, ret = NET_RX_DROP;
230 primary_if = primary_if_get_selected(bat_priv);
234 frag_skb = dev_alloc_skb(data_len - (data_len / 2) + ucf_hdr_len);
237 skb_reserve(frag_skb, ucf_hdr_len);
239 unicast_packet = (struct unicast_packet *)skb->data;
240 memcpy(&tmp_uc, unicast_packet, uc_hdr_len);
241 skb_split(skb, frag_skb, data_len / 2 + uc_hdr_len);
243 if (batadv_skb_head_push(skb, ucf_hdr_len - uc_hdr_len) < 0 ||
244 batadv_skb_head_push(frag_skb, ucf_hdr_len) < 0)
247 frag1 = (struct unicast_frag_packet *)skb->data;
248 frag2 = (struct unicast_frag_packet *)frag_skb->data;
250 memcpy(frag1, &tmp_uc, sizeof(tmp_uc));
253 frag1->header.version = COMPAT_VERSION;
254 frag1->header.packet_type = BAT_UNICAST_FRAG;
256 memcpy(frag1->orig, primary_if->net_dev->dev_addr, ETH_ALEN);
257 memcpy(frag2, frag1, sizeof(*frag2));
260 large_tail = UNI_FRAG_LARGETAIL;
262 frag1->flags = UNI_FRAG_HEAD | large_tail;
263 frag2->flags = large_tail;
265 seqno = atomic_add_return(2, &hard_iface->frag_seqno);
266 frag1->seqno = htons(seqno - 1);
267 frag2->seqno = htons(seqno);
269 batadv_send_skb_packet(skb, hard_iface, dstaddr);
270 batadv_send_skb_packet(frag_skb, hard_iface, dstaddr);
271 ret = NET_RX_SUCCESS;
280 hardif_free_ref(primary_if);
284 int batadv_unicast_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv)
286 struct ethhdr *ethhdr = (struct ethhdr *)skb->data;
287 struct unicast_packet *unicast_packet;
288 struct orig_node *orig_node;
289 struct neigh_node *neigh_node;
290 int data_len = skb->len;
293 /* get routing information */
294 if (is_multicast_ether_addr(ethhdr->h_dest)) {
295 orig_node = batadv_gw_get_selected_orig(bat_priv);
300 /* check for tt host - increases orig_node refcount.
301 * returns NULL in case of AP isolation
303 orig_node = batadv_transtable_search(bat_priv, ethhdr->h_source,
307 * - if orig_node is NULL it returns NULL
308 * - increases neigh_nodes refcount if found.
310 neigh_node = batadv_find_router(bat_priv, orig_node, NULL);
314 if (batadv_skb_head_push(skb, sizeof(*unicast_packet)) < 0)
317 unicast_packet = (struct unicast_packet *)skb->data;
319 unicast_packet->header.version = COMPAT_VERSION;
320 /* batman packet type: unicast */
321 unicast_packet->header.packet_type = BAT_UNICAST;
322 /* set unicast ttl */
323 unicast_packet->header.ttl = TTL;
324 /* copy the destination for faster routing */
325 memcpy(unicast_packet->dest, orig_node->orig, ETH_ALEN);
326 /* set the destination tt version number */
327 unicast_packet->ttvn =
328 (uint8_t)atomic_read(&orig_node->last_ttvn);
330 /* inform the destination node that we are still missing a correct route
331 * for this client. The destination will receive this packet and will
332 * try to reroute it because the ttvn contained in the header is less
333 * than the current one
335 if (batadv_tt_global_client_is_roaming(bat_priv, ethhdr->h_dest))
336 unicast_packet->ttvn = unicast_packet->ttvn - 1;
338 if (atomic_read(&bat_priv->fragmentation) &&
339 data_len + sizeof(*unicast_packet) >
340 neigh_node->if_incoming->net_dev->mtu) {
341 /* send frag skb decreases ttl */
342 unicast_packet->header.ttl++;
343 ret = batadv_frag_send_skb(skb, bat_priv,
344 neigh_node->if_incoming,
349 batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
355 batadv_neigh_node_free_ref(neigh_node);
357 batadv_orig_node_free_ref(orig_node);